Juan Manuel Marquez altered not one, but two boxing legacies on Saturday night with one overhand right hand to the grill of Manny Pacquiao late in the sixth round of their epic fourth bout.

Marquez's impressive and decisive knockout victory cemented Saturday's episode as the most thrilling between the two boxing adversaries. Although Pacquiao-Marquez hadn't lacked explosion nor entertainment since it began back in 2004, it was desperate for some confirmation.

Throughout the first 17-plus minutes, each fighter had his chances. Just when it seemed like Marquez was destined for a knockout early, Pacquiao would respond and rock Marquez with a quality shot of his own.

The action was superb throughout, but things really got interesting by the arrival of the third round.

Marquez got the crowd behind him in the third when he sent Pacquiao to the mat with a booming right cross. Pac-Man was lucky the fight didn't end right there.

But soon after, in the fifth round, Pacquiao forced Marquez to regain himself after connecting on a well-thrown left hand. Both boxers went back and forth early, making for some nervous moments.

The quick and often hectic pace made for several knockout opportunities for each fighter. Even Marquez was worried about the potential of being dropped according to this quote after the fight (via ESPN.com's Dan Rafael): "I knew Manny could knock me out at any time, I threw the perfect punch."

In the end, it was Marquez's brilliantly-timed, and yes, perfect counter punch in combination with Pacquiao's poor defense that ended the fight just midway through. The devastating overhand right from Dinamita put Pac-Man to sleep for a moment and confirmed Marquez's doubts about the previous results.

We can only hope that his highlight reel knockout will be enough to force a fifth episode in this epic fight saga.